So you want to create your own membrane keypad? Why? well making your own keypad can be useful for many reasons. It's cheap and easy to do, it can be placed in situations where it may be vandalized or stolen without much frustration, It can be fully customized to display whatever you like, and you can make as large a keypad as you like with as many inputs as you can handle. I created my keypad to go on the exterior of my door in residence to act as a keypad entry in much the same way as colin353 did here www.instructables.com/id/An-Electronic-Door-Opener/
. I however have some more tricks up my sleeve for this coming up in a later Instructable.
****NOTE: This is not a complete instructable for the time being. It goes through the construction of a keypad fully, however it does not yet fully explain or demonstrate the means to make it useful. This will change